The present invention relates to count control of a step counter for a data processing apparatus.
Recently, as the application field of digital computers has been greatly extended, users' demands for functions have been diversified. Consequently, operating systems for software have become very complicated. For this reason, structural analysis of an operating system cannot be performed only by desk work. As a means for performing this structural analysis, a step counter for counting a dynamic execution number of machine instructions is sometimes incorporated in a data processing apparatus.
In such a conventional data processing apparatus, a step counter counts machine instructions in units of processes. However, since a program for software generally has a hierarchical structure using subroutines, when minute analysis such as structural analysis of a specific subroutine is to be performed, a count control instruction for causing a step counter to count or stop counting is inserted in the software program in advance.
Since the above-described conventional step counter counts machine instructions in units of processes, when minute structural analysis is to be performed, a count control instruction for causing a step counter to count or stop counting must be inserted in a program for software in advance. Therefore, the conventional step counter has poor flexibility, and the processing speed is decreased.